You have missed semicolon in your skin1.css at line 332. This is the style for background color of "DialogTitle" style. Without semicolon this style is not applied, so the background not filled by blue color.
Attachment 1174 - see at this picture: I've added style via FireBug and DialogTitle displayed correctly. Here is your fixed CSS file:
Attachment 1175 but with another extension, please rename it to css instead of txt. Don't forget to clear the cache.